Fix Codex stream fallback for Responses completion gaps

tests/test_run_agent_codex_responses.py

@@ -144,6 +144,18 @@ class _FakeResponsesStream:
         return self._final_response
 
 
+class _FakeCreateStream:
+    def __init__(self, events):
+        self._events = list(events)
+        self.closed = False
+
+    def __iter__(self):
+        return iter(self._events)
+
+    def close(self):
+        self.closed = True
+
+
 def test_api_mode_uses_explicit_provider_when_codex(monkeypatch):
     _patch_agent_bootstrap(monkeypatch)
     agent = run_agent.AIAgent(
@@ -263,6 +275,42 @@ def test_run_codex_stream_falls_back_to_create_after_stream_completion_error(mon
     assert response.output[0].content[0].text == "create fallback ok"
 
 
+def test_run_codex_stream_fallback_parses_create_stream_events(monkeypatch):
+    agent = _build_agent(monkeypatch)
+    calls = {"stream": 0, "create": 0}
+    create_stream = _FakeCreateStream(
+        [
+            SimpleNamespace(type="response.created"),
+            SimpleNamespace(type="response.in_progress"),
+            SimpleNamespace(type="response.completed", response=_codex_message_response("streamed create ok")),
+        ]
+    )
+
+    def _fake_stream(**kwargs):
+        calls["stream"] += 1
+        return _FakeResponsesStream(
+            final_error=RuntimeError("Didn't receive a `response.completed` event.")
+        )
+
+    def _fake_create(**kwargs):
+        calls["create"] += 1
+        assert kwargs.get("stream") is True
+        return create_stream
+
+    agent.client = SimpleNamespace(
+        responses=SimpleNamespace(
+            stream=_fake_stream,
+            create=_fake_create,
+        )
+    )
+
+    response = agent._run_codex_stream({"model": "gpt-5-codex"})
+    assert calls["stream"] == 2
+    assert calls["create"] == 1
+    assert create_stream.closed is True
+    assert response.output[0].content[0].text == "streamed create ok"
+
+
 def test_run_conversation_codex_plain_text(monkeypatch):
     agent = _build_agent(monkeypatch)
     monkeypatch.setattr(agent, "_interruptible_api_call", lambda api_kwargs: _codex_message_response("OK"))